New desktop build Restarts/Shuts Down out of nowhere once a day

[bgen]

Hi ! So my pc keeps restarting / shutting down like 1/2 hours after i turn it on. It only does it every time it has been off for at
least one day . After i turn in back on it wont do it again for the rest of the day . Or for as long as i do not shut it down and leave it like that for 1 day aprox . I tested the ram with memtest86+ for 8 hours, no errors, checked the psu for cable issues everything seems fine, checked for virus and malwares , got none so far. CPU Temps on idle 29°C, MOBO Temps on idle 37 °C.

Volts:
12v ----- 12.192v
5v------- 4.960v
3.3v ----- 3.328v

The only "weird" thing i ve seen so far is that my 2 chassis fans connected to the MOBO appear as red with 400rpm in BIOS .I went to the monitor section in the UEFI and changed the minimum rpm fans to 200 but the red warning s still there.


Also i do not have the asus "recommended" ram settings for the MOBO sockets.

AX 850 gold PSU
I7 3820
Corsair H100
EVGA GTX 670 ftw
Asus sabertooth x79
2x4gb corsair vengeance 1866 mhz
Case Overseer RX-I
SDD vertex 4
WD 1TB Black Caviar
Razer Black widow ultimate
Cyborg M.M.O 7
Windows 7 home premium
AVG Anti Virus
MalwareBytes anti-malware

Any help please ? What could be causing this problem ?

 

[bgen]

Hello, just wanted to say that the problem came back. I suspected it was the Motherboard so i sent it for RMA . Recently installed the new one and so far its been as perfect as it should be. No problems at all, everything runs smoothly.

So ill leave here the symptons my computer had :

-Restarts out of nowhere everytime i turned on the pc after it was off for several hours.
-Problems with drivers recognition coming back from sleep mode . I had to kinda reset the computer everytime i forgot and let it felt into sleep mode.
-Memory ram recognition. Only recognized half of it.

that was my case, hope it helps.